Symposium Organizers
Milos Nesladek Academy of Sciences of the Czech Republic
Institute of Physics
Philippe Bergonzo CEA
James E. Butler (Retired)
Richard B. Jackman University College London
Kian Ping Loh National University of Singapore
J1: Towards Diamond Nanotechnology
Session Chairs
Monday PM, November 30, 2009
Back Bay A (Sheraton)
10:00 AM - **J1.1
Nanoelectronics Roadmap and the Opportunities for Carbon Based Electronics in the Diversification.
Simon Deleonibus 1
1 , CEA LETI, Grenoble France
Show AbstractThe microelectronics industry is facing historical challenges to down scale CMOS devices through the demand for low voltage, low power, high performance and increased functionalities[1]. The implementation of new materials and devices architectures will be necessary. HiK gate dielectric and metal gate are among the most strategic options to reduce power consumption and manage low supply voltage. Multigate , multichannels[2], sub 60mV/dec swing architectures[3] based on wrapped around nanowires increase MOSFETs drivability, reduce power at the Lg=5nm level, and allow new memory devices opportunities. By introducing new materials(HiK, Ge, III-V, Carbon based materials like diamond, graphene and CNTs, molecules,…), and new functions such as sensing and actuation allowing to interface the outside world (M/NEMS, filters, Imagers,…), Si based CMOS will be pushed beyond the ITRS as the System-on-Chip/Wafer Platform[4] The Heterogeneous co-integration of these devices with CMOS can be added to new 3D and Packaging schemes leading to the increase of effective packing density, functionalities and improve systems figures of merit[5, 6].References[1] Electronic Device Architectures for the Nano-CMOS Era From Ultimate CMOS Scaling to Beyond CMOS Devices. Editor: S.Deleonibus, Pan Stanford Publishing, Nov 2008[2] C.Dupré et al., IEDM 2008,p748-751[3] F.Mayer et al., IEDM 2008, p163-166 and C.Le Royer et al.,.ULIS 2009 , pp:53 – 56, Dig. Object Id. 10.1109/ULIS.2009.4897537[4] T.Ernst et al. , IEDM 2008, invited talk, p745-748[5] P. Batude et al., VLSI Tech Symposium 2009, pp.166-167. [6] N.Sillon et al. IEDM 2008, invited talk, p595-597.
10:30 AM - **J1.2
High-Speed Coherent Control of Single Spins in Diamond.
G. Fuchs 1 , F. Heremans 1 , D. Toyli 1 , V. Dobrovitski 2 , C. Weis 3 , T. Schenkel 3 , David Awschalom 1
1 Center for Spintronics and Quantum Computation, University of California, Santa Barbara, California, United States, 2 , Ames Laboratory and Iowa State University, Ames, Iowa, United States, 3 , Lawrence Berkeley National Laboratory, Berkeley, California, United States
Show AbstractNitrogen vacancy (NV) centers in diamond are emerging as a promising system for spin-based applications in quantum information and communication at room temperature. Using a combination of confocal microscopy and spin resonance, the spin of individual NV centers can be initialized, manipulated and read out. These techniques have been used to study the long room temperature spin coherence times of NV centers, their coherent interactions with individual dopants, and the interactions of a single spin with its environment [1]. Progress in the growth of high-quality, single-crystal diamond continues to fuel efforts in developing this material as a platform for solid state technologies. There remain significant challenges, however, both in understanding the physics of these defects as well as the development of technologies based on their quantum properties. We describe experiments aimed at spin-engineering this system using spatially and isotopically selective ion implanting techniques into synthetic films [2]. Using single-spin resonant spectroscopy, we observe the electron spin levels of implanted spins and find strong hyperfine coupling to the nitrogen nuclear spin in the excited state [3]. Finally, we extend coherent control of individual spins to the chip level with the fabrication of coplanar waveguide structures onto diamond substrates. The ability to drive these devices at high Rabi frequencies enables single electron spin flips within a few precessional cycles. Within large driving fields, conventional models of spin dynamics break down, offering new research opportunities in this regime.[1] R. Hanson, et al., Science 320, 352 (2008).[2] C. D. Weis et al., J. Vac. Sci. Tech. B 26, 2596 (2008).[3] G. D. Fuchs et al., Phys. Rev. Lett. 101, 117601 (2008).
J2: Quantum Diamond I
Session Chairs
Monday PM, November 30, 2009
Back Bay A (Sheraton)
11:30 AM - **J2.1
Single Spins in Diamond for Quantum Information Procesing and Magnetometry.
Fedor Jelezko 1 , Joerg Wrachtrup 1
1 , Physics Department, University of Stuttgart, Stuttgart Germany
Show AbstractDiamond is continiously attracting attention of material scientist owing to unprecedented thermal conductivity, high charge carrier mobility and chemical inertness. Less known is that defects in diamond can be used for quantum information processing. Owing to their remarkable stability, colour centers in diamond have already found an application in quantum cryptography. In this talk I will discuss recent progress regarding spin-based quantum information processing and atomic magnetometry.ReferencesBalasubramanian, G. et al. Ultralong spin coherence time in isotopically engineered diamond. Nature Materials DOI: 10.1038/NMAT2420 (2009)Balasubramanian, G. et al. Nanoscale imaging magnetometry with diamond spins under ambient conditions. Nature 455, 648-651 (2008).Neumann, P. et al. Multipartite entanglement among single spins in diamond. Science 320, 1326-1329 (2008).
12:00 PM - J2.2
Dynamic Polarization of Single Nuclear Spins in a Room Temperature Diamond.
Jacques Vincent 1 2 , Philipp Neumann 1 , Johannes Beck 1 , Fedor Jelezko 1 , Joerg Wrachtrup 1
1 , PI3, Stuttgart University, Stuttgart Germany, 2 , LPQM, Ecole Normale Supérieure de Cachan, Cachan France
Show AbstractRecently, room temperature readout of single nuclear spins in diamond has been achieved by coherently mapping nuclear spin states onto the electron spin of a single NV color center [1], which can be optically polarized and read-out with long coherence time [2]. This has been the basis for spectacular experiments in quantum information science, ranging from the implementation of a nuclear-spin-based quantum register [3], a conditional two-qubit CNOT gate [4], and very recently the generation of Bell and GHZ states with extraordinarily long coherence times [5], even at room temperature.However, most of these experiments were performed without any deterministic polarization of nuclear spin states [4-5]. This random initialization unavoidably decreases the success rate of all local operations as 1/2N where N is the number of qubits. Deterministic polarization of the nuclear spins thus appears as a crucial step toward development of a scalable diamond based quantum information processing unit.We report a versatile method to efficiently polarize single nuclear spins in diamond, which is based on optical pumping of a single NV color center and mediated by a level-anti crossing in its excited state [6-7]. A nuclear spin polarization higher than 98% is achieved at room temperature for the 15N nuclear spin associated to the NV center, corresponding to μK effective nuclear spin temperature. We then show simultaneous deterministic initialization of two nuclear spins (13C and 15N) in close vicinity to a NV defect, which provides efficient initialization of a three qubit quantum register by including the electron spin [7]. Such robust control of nuclear spin states is a key ingredient for further scaling up nuclear-spin based quantum registers in diamond.References:[1] L. Childress et al., Science 314, 281 (2006).[2] G. Balasubramanian et al., Nature Materials 8, 383 (2009).[3] M. V. Gurudev Dutt et al., Science 316, 1312 (2007).[4] F. Jelezko et al., Phys. Rev. Lett. 92, 076401 (2004). [5] P. Neumann et al., Science 320, 1326 (2008)[6] P. Neumann et al., New. J. Phys. 11, 013017 (2009).[7] V. Jacques et al., Phys. Rev. Lett. 102, 057403 (2009).
12:15 PM - J2.3
Generation of Single Spins in Diamond using Ion Implantation.
David Toyli 1 , G. Fuchs 1 , F. Heremans 1 , C. Weis 2 , T. Schenkel 2 , D. Awschalom 1
1 Center for Spintronics and Quantum Computation, University of California, Santa Barbara, Santa Barbara, California, United States, 2 , Lawrence Berkeley National Laboratory, Berkeley, California, United States
Show AbstractNitrogen-vacancy (N-V) defect centers in diamond have garnered increasing attention for quantum information science applications in recent years. N-V centers are an apt candidate for such applications because of their long room temperature spin coherence times and their capacity to have their spin states optically initialized and read out at room temperature. However, the desire to further apply N-V center spins in quantum information science experiments necessitates the development of a means to reliably position N-V centers within the diamond host. We address this challenge by using scanning probe aligned ion beams to controllably generate N-V centers with both spatial and isotopic control [1]. We describe experiments aimed at understanding the formation dynamics of N-V centers in single-crystal synthetic diamond and ways to enhance their creation efficiency through optimization of nitrogen implantation parameters, annealing, and co-implantation of argon ions to create additional vacancies within the diamond lattice. Furthermore, we demonstrate the implantation of N-V centers near the single-defect limit using apertures in scanning force microscope tips. [1] C. D. Weis et al., J. Vac. Sci. Tech. B 26, 2596 (2008).
12:30 PM - J2.4
Optically Detected Magnetic Resonance of a Single Spin Associated to a Single NV Color Center in Diamond Nanocrystals.
Ngoc Diep Lai 1 , Dingwei Zheng 1 2 , Vincent Jacques 1 , Fedor Jelezko 3 , Francois Treussart 1 , Jean-Francois Roch 1
1 , Laboratoire de Photonique Quantique et Moléculaire, Ecole Normale Supérieure de Cachan, Cachan France, 2 , State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai China, 3 , 3.Physikalisches Institut, Universitat Stuttgart, Stuttgart Germany
Show AbstractControlled and coherent manipulation of individual quantum systems is a fundamental key for the development of quantum information processing. The Nitrogen-Vacancy (NV) color center in diamond has been identified as a unique system offering individual electron spin control and very long phase memory time at room temperature. In order to apply to applications as spin-resonance-based magnetometry or multiple-spins-based quantum computer, the understanding and the control of electron spin resonance (ESR) of a single NV center in a diamond nanocrystal is required. We report the application of optically detected ESR to determine the orientation of an arbitrary NV single spin. Indeed, the electron spin state of a single NV color center is optically readout by a decrease of luminescence when the applied microwave frequency is adjusted to the resonance frequency. Application of an external magnetic field by changing its amplitude and its orientation, allows to determine the orientation (theta, phi) of the electron spin. Following this determination, we change the excitation polarization in order to determine the transition dipoles associated to a single NV color center. We experimentally confirm that the NV color center has two orthogonal dipoles, which are in a plane perpendicular to the NV-center spin axis in the diamond matrix. Determination of dipole emission structure is important to optimize the coupling of NV-center luminescence to microstructures, like plasmonic antennas and photonic crystals
12:45 PM - J2.5
Fabrication of Diamond Nanostructures for Quantum Information Processing Applications.
Birgit Hausmann 1 2 , Mughees Khan 1 , Tom Babinec 1 , Yinan Zhang 1 , Phil Hemmer 3 , Marko Loncar 1
1 School of Engineering and Applied Science, Harvard University, Cambridge, Massachusetts, United States, 2 Department of Physics, Technische Universität München, D-85748 Garching Germany, 3 Department of Electrical and Computer Engineering, Texas A&M University, College Station, Texas, United States
Show AbstractWe have developed a top-down nanofabrication process for producing nanowires in a single crystal diamond substrate. First, a thin layer of FOx e-beam resist (spin-on glass) was spun on to both HPHT Ib and CVD IIa synthetic diamond samples. E-beam lithography was then used to define arrays of circular pillar shaped mask with varying diameters on the diamond surface. This mask was then transferred into the diamond via an inductively coupled oxygen plasma reactive ion etch. A near-vertical etch profile was achieved for 4µm long nanowires with 60-350nm diameters. Slight variations in the etching properties of different diamonds resulted in Ib and IIa diamonds having a 200nm/min and 240nm/min etch rate, respectively. In either case, the etch rate of the FOx was less than 10nm/min for the parameters used, making it a suitable mask for diamond nanofabrication work. We will describe other masking and etching procedures that were found to be less ideal. Nitrogen-vacancy color centers are distributed throughout the diamond sample and are randomly positioned in these diamond structures. The presented single crystal diamond nanowires have been shown elsewhere to be efficient single photon sources for quantum cryptography and quantum information processing applications. Finally, we will also present our recent work on developing fabrication procedures for other single crystal diamond nanostructures, including hybrid diamond-plasmon devices. References:B. Hausmann et. al., Fabrication of Diamond Nanowires for Quantum Information Processing Applications, Submitted to Diamond and Related Materials.T. Babinec et. al., An Efficient Single Photon Source Based on a Diamond Nanowire, In Preparation
J3: Diamond Nanoscale Sensors
Session Chairs
Monday PM, November 30, 2009
Back Bay A (Sheraton)
2:30 PM - **J3.1
Nanodiamonds and Their Bioapplications.
Chia-Liang Cheng 1
1 department of Physics, National Dong Hwa University, Hualien Taiwan
Show AbstractNanodiamond (ND) has emerging to be an important nanomaterial for bio- and medical applications due to their superb physical and chemical properties. Bio molecules can be immobilized on the diamond surface via various chemical/physical methods. The recent proved biocompatibility renders ND promising application in bio systems. We propose to use nanodiamond as a biocompatible nanoparticle for bio labeling of bio molecule’s interaction with cells. For this purpose, ND’s spectroscopic properties, such as unique Raman signal and its natural fluorescence, are used a bio markers to probe the interactions of bio molecules with cell and bacteria in the single cellular level. The surface spectroscopy of nanodiamonds could be analyzed using infrared and Raman spectroscopy. The biocompatibility, ND interaction with cells and detection are evaluated for various sizes NDs on human lung A549 epithelial cells and HFL-1 normal fibroblasts. ND did not reduce the cell viability and alter the protein expression profile in the test cells.In this report, we demonstrate several cases of the interaction of ND with cells. Different methods were developed to functionalize the surface of nanodiamond with various functional groups, which allow further conjugation with bio molecules via either physical (electrostatic interaction) or chemical (covalent bonding) interactions. The developed ND-biomolecule conjugate serves as a nano-bio-probe to label bio-interaction. We successfully used nanodiamond to label the interaction of growth hormone (GH) and growth hormone receptor (GHR) on human lung cancer cell (A549) membrane surface. In a second case, we labeled the interaction of protein Lysozyme with bacteria E. coli using nanodiamonds. ND conjugating with alpha-bungarotoxin (α-BTX), a neurotoxin derived from Bungarus multicinctus with specific blockade of alpha7-nicotinic acetylcholine receptor (α7-nAChR). The cND-α-BTX was observed by imaging and binding to the α7-nAChR in Xenopus laevis’s oocyte and lung cancer cell. The cND–α-BTX can be visualized on the targeting cells and executes the biological function to block the activation of α7-nAChR. Other cases such as anti-cancer drugs were conjugated to ND surface to interact with lung cancer cells; the results suggest anti-cancer drug’s functionality is still preserved for efficient drug treatments.The success of these experiments demonstrated nanodiamond’s great potential in bio/medical applications; based on the properties of uptake ability, delectability and little cytotoxicity in human cells.
3:00 PM - J3.2
In-situ Monitoring of Cytochrome C Adsorption on Diamond Using Scanning Probe Microscopy.
Susanne Kopta 1 , Nianjun Yang 1 , Armin Kriele 1 , Rene Hoffmann 1 , Waldemar Smirnov 1 , Christoph Nebel 1
1 Micro- and Nano-Sensors, Fraunhofer Institute for Applied Solid State Physics IAF, Freiburg Germany
Show AbstractBiofunctionalized diamond surfaces attract increased attention, due to the biocompatibility and chemical inertness of diamond. For sensor applications the adsorption of large biomolecules like DNA, proteins and enzymes on substrate surfaces is in some cases intended and in others undesirable. The latter is for example the case when a layer of bio-molecules permanently covers a sensor area and blocks further molecules from interacting. Thus it is crucial to control the surface properties. For diamond different surface terminations can be applied which allows to change the properties from hydrophobic for H-termination to hydrophilic for O-termination. There is an ongoing discussion, if a hydrogen-terminated compared to an oxygen-terminated diamond surface has the ability to block unintentional adsorption of proteins, or if additional functionalization is required. In this contribution we will present results with respect to adsorption properties of the enzyme “cytochrome C” as measured on hydrogen-, hydroxyl- and oxygen-terminated atomically flat diamond surfaces in physiological buffer solution. We applied atomic force microscopy (AFM) to monitor adsorption characteristics in combination with electrochemical measurements which detect the redox activity of enzymes. These results indicate that H-termination prevents the adsorption of this protein to diamond. We will present measurements obtained on lithographically patterned highly boron-doped diamond-surfaces with H-, OH- and O-terminated areas in close vicinity. These areas are of a few micrometers in size. The mechanism for the adsorption of cytochrome C on such different diamond surfaces will be discussed in detail and compared with those obtained on other substrates.
3:15 PM - J3.3
Surface Functionalization of Nanodiamond for Composite and Biomedical Applications.
Vadym Mochalin 1 , Ioannis Neitzel 1 , Christopher Klug 2 , Yury Gogotsi 1
1 Materials Science and Engineering, Drexel University, Philadelphia, Pennsylvania, United States, 2 Chemistry Division, Naval Research Laboratory, Washington, District of Columbia, United States
Show AbstractNanosized diamond powders (nanodiamond or ND), produced by detonation synthesis in large volumes mainly by Russia, China, Japan, and European countries, represent a novel relatively inexpensive carbon nanomaterial with many unexplored capabilities and a broad range of potential applications, such as drug delivery and biomedical imaging, composite materials, lubricants, polishing and cooling liquids, etc. ND is composed of particles of ~5nm in diameter consisting of an inert diamond core with covalently bonded surface functional groups such as C=O, COOH, OH etc. In as-produced material, which usually needs to be purified prior to use, the diamond core is surrounded by graphitic shells and amorphous carbon.The major differences and unique properties of ND compared to other carbon nanomaterials, such as carbon nanotubes, are due to its large accessible and reactive surface bearing a large variety of surface functional groups. Thus, surface modification is a key stage in development of any applications of ND. We develop various purification and surface modification techniques for ND in order to tailor it for advanced composite and biomedical applications. Using Scanning Electron Microscop, High Resolution Transmission Electron Microscopy, nanoindentation, NMR, IR, and Raman spectroscopy, we demonstrate that purified ND with tailored surface chemistry can be used to produce ND-containing polymer nanofibers with up to 60 % wt. of ND. ND powders containing amino groups on the surface can be used to produce ND-epoxy composites with covalent bonds between the epoxy matrix and ND particles. ND with covalently bonded octadecylamine (ODA) chains is highly hydrophobic and demonstrates bright blue fluorescence in UV light. It can be used as a non-toxic substitute of fluorescent semiconductor quantum dots for in vivo biomedical imaging as well as an additive to oils, fuels, and in any application where dispersions of ND in hydrophobic environment are required.
3:30 PM - J3.4
Study of Formation V-N Complexes in Irradiated Diamond by using a Combination of Defects Spectroscopy: PAS, PL.
Marie-France Barthe 1 , Jacques Botsoa 1 2 , Elisa Leoni 1 , Thierry Sauvage 1 , Pierre Desgardin 1 , Francois Treussart 2
1 CEMHTI, CNRS, Orléans France, 2 LPQM, UMR8537 CNRS Ecole Normale Supérieure de Cachan, Cachan France
Show AbstractThe development of novel nanometric photoluminescent probes is a very active research field considering their numerous applications, such as for chemical sensing, bio probes, photo-markers etc… The best probe must exhibit a very small size, ideally <20 nm, further to a strong and stable luminescence. Photoluminescent diamond nanocrystals have been produced and have demonstrated some interesting properties for these applications. In this work we have performed experiments to better understand and control the formation of V-N complexes in diamond single crystals. Several HPHT type 1b diamond samples from Element 6 have been irradiated with 2.4 MeV protons at fluences in the range from 5x1015at/cm2-1x1017at/cm2 . These samples have been characterized after irradiation and for some after post annealing by using a combination of defect spectroscopy. Slow positron beam based Doppler annihilation-ray broadening spectrometry (SPBDB) -performed at CEMHTI (Orléans)- and Photoluminescence – performed at LPQM (Cachan) have been used to characterize the first microns under the surface. SPBDB has shown that vacancy defects are detected after irradiation. Their concentration depends on the fluence of protons. Negatively charged and neutral V-N complexes have been detected after annealing in different conditions by using PL. The influence of the proton fluence and of the temperature and duration of post annealings on the formation of the V-N centers will be discussed.
3:45 PM - J3.5
Functionalised Nanodiamond Luminescence Study.
Irena Kratochvilova 1 , Andrew Taylor 1 , Ivan Gregora 1 , Frantisek Fendrych 1 , Anke Krueger 2 , Milos Nesladek 3 4
1 , Institute of Physics, Prague 8 Czechia, 2 , Institute for Organic Chemistry, Julius-Maximillian- Universität, Würzburg Germany, 3 , Hasselt University, Institute for Materials Research (IMO, Diepenbeek Belgium, 4 , IMEC vzw, Division IMOMEC, Diepenbeek Belgium
Show AbstractDynamic information about biomolecular processes inside living cells is important for fundamental understanding of cellular functions. In order to further progress in this field, specifically for monitoring genomic processes, there is now an immense need for the development of novel sensing and detection techniques that can operate at submicroscopic resolution inside living cells and at the same time yield real-time information about local biomolecular interactions. Nanodiamond (ND) particles can penetrate through the cell membrane and can be used as in cell sensors working mainly on optical detection methods such as luminescence. To enable grafting of complex bio-molecules (e.g. DNA) the surface of the ND require specific functionalisations (e.g. H, OH) were used. However, the band bending at the surface of diamond can be easily induced by a specific functionalisation. For nanoparticles of a small size, the surface Fermi-level pinning can be of importance for changing the occupation of the N-V centres and leading consequently to luminiscence quenching due to relative weight changes of NV0 and NV- centres occupation. To study these effects we have prepared variously terminated ND surfaces from synthetic ND of 20-50 nm size. NV0 and NV- related luminescence is observed in untreated and carbonyl terminated ND. H terminated ND show very low NV luminescence. After annealing to remove the H surface hydrogen, converging to oxidised surface the NV0 and NV- related luminescence is again observed.
J4: Thermal and Mechanical Applications of Diamond
Session Chairs
Monday PM, November 30, 2009
Back Bay A (Sheraton)
4:30 PM - J4.1
Study and Optimization of Silicon-CVD Diamond Interface for SOD Applications.
Jean-Paul Mazellier 1 3 , Jean-Charles Arnault 2 , Julie Widiez 1 , Mathieu Lions 1 2 , Francois Andrieu 1 , Robert Truche 1 , Samuel Saada 2 , Philipe Bergonzo 2 , Simon Deleonibus 1 , Sorin Cristoloveanu 3 , Olivier Faynot 1
1 , CEA-LETI MINATEC, Grenoble France, 3 , IMEP-LAHC MINATEC, Grenoble France, 2 , CEA-LIST, Saclay France
Show AbstractNowadays, semiconductor industry is facing an exciting challenge concerning its future. Not only transistor size shrinking is to be overcome but also innovative integration of new architectures and functionalities are to be managed. This advanced integration requires solutions to problem that were not addressed up to now. Thermal management at the device scale is part of this new era that needs smart solutions. Especially concerning Silicon-On-Insulator (SOI) substrates: this technology offers lots of advantages for advanced devices such as easy processing but also enhanced static and dynamic electric control. Nevertheless, standard Buried OXide (BOX) layer is a supplementary issue in terms of thermal management (kSiO2 = 1.4W/mK compared to kSi = 150W/mK). Some works have already focused on alternative material for BOX replacement, by integrating CVD diamond layers, but without any proof of thermal amelioration [1].We propose here to replace the standard BOX by thin CVD diamond layer, forming Silicon-On-Diamond substrate (SOD). In order to optimize the final SOD, we have looked to optimize the silicon-diamond interface in order to keep the excellent performances of SOI structure. This grown has been done directly on silicon or by using an intermediate stack between both materials. This stack integrates very thin SiO2 in the vicinity of silicon in order to keep the extremely good electrical quality of the Si-SiO2 couple and to manage near-coupling effects in advanced MOSFETs. But hydrogen plasma used in CVD diamond deposition being very reactive with SiO2 different capping layers (polysilicon, Si3N4, Pt) have been envisaged to both allow diamond seeding and to protect the underlying oxide layer. Electrical and thermal simulations have been run to support our integration scheme, supporting the idea of 10 to 20nm thick SiO2 co-integrated with 200nm diamond layer. We have also characterized our substrates by SEM and HRTEM observations: we have controlled that no degradation is induced in silicon by direct deposition and that the oxide layer is well protected by the cappings. XPS analyses have been performed to control the stability of the substrate stack for the different schemes. Furthermore, electrical and thermal properties have been measured and show both high insulation (up to 10^14Ω.cm) and enhanced thermal performances over simple standard oxide layer, reducing by more than 3 to 10 the associated thermal resistance.[1] B. Edholm, L. Vestling, M. Bergh, S. Tiensuu and A. Söderbärg, “Silicon-On-Diamond MOS-Transistors with Thermally Grown Gate Oxide”, Proceedings IEEE International SOI Conference, 1997
4:45 PM - J4.2
Thermal Management in GaN HEMTs via Heterogeneous Integration Using Micro-transfer Printing with Advanced Thin Film Diamond Thermal Materials.
John Carlisle 1 , Hongjun Zeng 1 , Hoon-sik Kim 2 , John Rogers 2 , Etienne Menard 3 , Steven Dooley 4 , Jesse Jur 5 , Mark Johnson 5 , Edwin Piner 6
1 , Advanced Diamond Technologies, Inc., Romeoville, Illinois, United States, 2 Materials Science & Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States, 3 , Semprius, Durham, North Carolina, United States, 4 AFRL/RYDI, Wright Patterson AFB, Dayton, Ohio, United States, 5 Materials Science & Engineering, North Carolina State University, Raleigh, North Carolina, United States, 6 , Nitronex Corporation, Durham, North Carolina, United States
Show AbstractThermal management is an increasingly important problem facing the semiconductor industry at the device, component, and system levels. For GaN-based High Electron Mobility Transistor (HEMT) power amplifiers, current device-level thermal spreading solutions place specific limits on the performance of these devices and also increases manufacturing costs by lowering the overall power density at which they can operation. Over the past several years wafer-scale solutions based on relatively thick (~100 micron) diamond films deposited on silicon wafers have been successfully integrated with GaN devices via wafer-bonding or direct deposition, with clear improvements in the thermal flux per unit area that can be handled while maintaining a constant junction temperature (~150 °C). However, there are several key technical challenges to scaling this technology, in particular the need to carefully control the residual and differential stress in the diamond film as deposited on the silicon wafer, in order to accommodate the wafer bonding process. In this presentation we discuss our initial work to utilize a completely different integration strategy to integrate diamond thin films with GaN devices based on micro-transfer printing. In our approach, high thermal conductivity thick (50 microns) and thin (2 micron) diamond films are placed within a few hundred nanometers above and below the junctions of active GaN HEMT devices. This is accomplished through a combination of microfabrication techniques performed at the wafer scale on the GaN and diamond substrates followed by transfer printing of singulated strips of GaN or diamond directly on top each other. The resulting diamond/GaN HEMT/diamond heterostructures are similar to that achieved via other approaches, but are realized with much greater manufacturing efficiency (lower cost) in addition to equivalent or superior thermal performance. A 3D thermal model was also developed that clearly demonstrates the feasibility of this approach. *This work was supported in part by the US Defense Advanced Research Projects Agency (DARPA).
5:00 PM - J4.3
High Young’s Modulus and Fracture Strength in Nanocrystalline Diamond.
Oliver Williams 1 , Armin Kriele 1 , Marco Wolfer 1 , Wolfgang Mueller-Sebert 1 , Christoph Nebel 1
1 , Fraunhofer IAF, Freiburg Germany
Show AbstractNanocrystalline diamond (NCD) has provided a cheap and simple way to exploit the many extreme properties of diamond for a diverse array of applications. Many of the desirable properties of diamond such as its hardness, chemical resilience make it difficult to manipulate and thus it has remained unexploited in some application areas. NCD bypasses many of these restrictions by realising a thin film of diamond on a foreign substrate, with many properties approaching those of single crystal diamond.One of the key mechanical properties of interest is the Young’s Modulus of diamond, which has a direct influence on resonant frequencies and quality factors of Micro ElectroMechanical Systems. How the Young’s Modulus of NCD if affected by CVD growth parameters has been largely uncharacterised up to now and this is the main goal of this work. In this work the characterisation of Young’s Modulus by membrane bulging will be demonstrated. Free standing membranes of 150 nm thick NCD show very high fracture strength and tolerate overpressures of > 2.5 bar. The variation of the Young’s Modulus, residual stress and surface roughness will be shown as a function of methane concentration at two different power densities. Young’s Modulus values as high as 1100 GPa will be demonstrated in films with surface roughness below 5 nm rms. The control of residual stress from tensile to compressive will also be demonstrated.
5:15 PM - J4.4
Integration of Pb (Ti0.52Zr0.48)O3 on Single Crystal Diamond.
Meiyong Liao 1 , Kiyomi Nakajima 2 , Masataka Imura 3 , Yasuo Koide 1 2
1 Sensor Materials Center, National Institute for Materials Science, Tsukuba Japan, 2 Nano-Innovation Center (NICe), National Institute for Materials Science , Tsukuba, Ibaraki, Japan, 3 International Center for Young Scientist, National Institute for Materials Science , Tsukuba, Ibaraki, Japan
Show AbstractDiamond is an attractive material for micro or nano-electro-mechanical system (M/NEMS). It possesses the highest acoustic velocity among all the materials, high thermal conductivity, exceptional wear resistance, and chemical inertness. The M/NEMS actuator/resonator manufactured from diamond can overcome the drawbacks of silicon, which has relatively poor physical, chemical, and mechanical properties. Despite the great progress in diamond MEMS, all the devices had been based on polycrystalline or nano-crystalline diamond. The current achievement in microwave plasma chemical vapor deposition offers the possibility to use high-quality single crystal diamond for M/NEMS devices. To achieve the applications of diamond to M/NEMS, the integration of piezoelectric materials on diamond is of prior importance. Lead zirconate titanate Pb(ZrxTi1-x)O3 (PZT) is an excellent piezoelectric material with high electromechanical coupling coefficient and electrical polarization. The integration of PZT on diamond offers the opportunity of actuating with low voltage and sensing of the displacement for a diamond cantilever or bridge. In this presentation, pizeoelectric PZT thin films are integrated on single crystal diamond (100) substrates by radio-frequency sputter deposition combing with post thermal annealing. The structure and the in-plane polarization of the PZT film are investigated with regard to the Al2O3 buffer layer and SrTiO3 seed layer. The electrical properties of the metal-ferroelectric-insulator-semiconductor capacitor using boron-doped single crystal diamond epilayer will also be discussed.
5:30 PM - J4.5
Novel Approaches for Diamond Micro-transducer Fabrication for Bio-chemical Sensing.
Alexandre Bongrain 1 , Emmanuel Scorsone 1 , Lionel Rousseau 2 , Gaelle Lissorgues 2 , Samuel Saada 1 , Charles Agnes 1 , Philippe Bergonzo 1
1 , CEA-LIST, SACLAY, Gif-sur-YVette France, 2 , ESIEE-ESYCOM University Paris Est, Noisy le Grand France
Show AbstractWe report on novel MEMS micro-transducers made of diamond and used for bio-sensing applications, and taking advantage of diamond remarkable mechanical hardness, strong chemical inertness and high Youngs modulus. However, micro-machining diamond using conventional processes is not as straightforward as it is for silicon. To overcome this drawback, we developed an original process involving the controlled growth of diamond on nanoparticle seeding patterns using the CVD (chemical vapour deposition) technique, inside micro-machined silicon moulds.Typical MEMS structures were successfully fabricated and include cantilevers and bridges. They were actuated using Laplace forces. In this way, gold tracks were deposited by photolithography along the edges of the structures in order to make a current loop. The actuation was operated by injecting an alternative current through the gold tracks while a permanent in-plan magnetic field orthogonal to the current was set near the structure. The measurement of the structures actuation was carried out by laser interferometry.The combination of diamond MEMS with patterned growth of boron doped layers on top of the structures enables electrochemical grafting of specific receptors for bio-detection. Novel biosensors fully made of diamond were successfully fabricated using this technique. We characterized our structures by measuring their resonance frequencies and the amplitude of the deflection with respect to the injected current. To check the validity of the measurement, we modelized and simulated our structures on Coventor-ware and compared the data with the measured values.
5:45 PM - J4.6
Growth and Processing of Diamond Films Grown on Ir(100) Surfaces for MEMS Applications.
Thomas Friedmann 1 , John Sullivan 1 , Subhash Shinde 1 , Edward Piekos 1
1 , Sandia National Laboratories, Albuquerque, New Mexico, United States
Show AbstractChemical vapor deposited (CVD) diamond films can be patterned and processed into simple microelectromechanical machines (MEMS) using standard micromachining techniques. Improved nucleation of diamond on (100) oriented Iridium surfaces has led to the development of higher crystalline quality oriented diamond films. These films should have improved mechanical, electrical, and thermal properties over more conventional CVD grown films motivating this study of their use in MEMS devices.The focus of this presentation will be on growth and processing of diamond films into simple MEMS devices suitable for simple mechanical and thermal property measurements. The diamond films are grown on sputtered Ir(100) oriented films grown on a pulsed laser deposited YSZ(100) oriented buffer layer on silicon. MEMS devices are patterned with an aluminum hard mask using lift-off followed by diamond etch in an oxygen plasma. Further etching of the Ir and YSZ layers is done in a CF4 plasma. The resulting structures are released by an isotropic silicon etch that undercuts the structures. Control of stress and stress gradients is important for successful device fabrication, and an in situ technique has been employed to measure the stress during nucleation and deposition. The magnitude of in-plane biaxial stress can be changed by altering the growth temperature and the methane to hydrogen ratio. Stress gradients through the film thickness can be caused by the evolution of the columnar grain structure that can be influenced by the nucleation conditions. This work was supported by the DOE Office of Basic Energy Sciences, Division of Materials Science and Engineering and by a Laboratory Directed Research and Development project at Sandia National Laboratories. Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the US Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.
Symposium Organizers
Milos Nesladek Academy of Sciences of the Czech Republic
Institute of Physics
Philippe Bergonzo CEA
James E. Butler (Retired)
Richard B. Jackman University College London
Kian Ping Loh National University of Singapore
J5: Progress in CVD Diamond Growth
Session Chairs
Tuesday AM, December 01, 2009
Back Bay A (Sheraton)
9:30 AM - **J5.1
Diamond Coated Graphite for Fusion Reactor Diverters.
Phillip John 1 , Samuele Porro 1 , Isaela Villalpando 1 , John Wilson 1 , Steve Lisgo 2 , Greg De Temmerman 2 , Bob Johnson 3 , Jerry Zimmer 3
1 School of Engineering & Physical Sciences, Heriot-Watt University, Edinburgh United Kingdom, 2 UKAEA Euratom Fusion Association, Culham Science Centre, Oxfordshire United Kingdom, 3 sp3 Inc, 2220 Martin Avenue, Santa Clara , California, United States
Show AbstractFusion offers the prospect of an almost limitless source of energy. In order to realise a secure energy scenario for future generations, some formidable scientific and engineering challenges need to be overcome. Magnetically confined fusion reactors, Tokamaks, produce high fluxes of energetic particles, massive radiation and thermal loads especially on the plasma facing components. The particle fluxes and heat fluxes onto solid surfaces lead to physical sputtering and chemical erosion and release surface material that has a deleterious affect on the plasma. Whilst graphite has desirable electrical and thermal properties as a low Z-diverter material in Tokamak reactors, the erosion and dust formation rates are detrimental to the operating conditions of the reactor.Diamond has been proposed [1] as an alternative material for the plasma facing surfaces of fusion reactors since it is more resistant to hydrogen plasma etching than graphite. The advent of hot filament and plasma technology that can deposit diamond over large areas has made this concept a more realistic prospect. We have reported on the first exposures [2], to the best of our knowledge, of CVD diamond layers on W and fusion grade graphite to fusion plasmas and similar conditions in MAST (UK), DIII-D (USA) and Pilot-PSI (Netherlands). This paper will report on the results of the pre- and post -exposure characterisation of the diamond layers by SEM, Raman spectrometry and XPS. Despite the thermal loading, the films did not delaminate and that the plasma etch rate was less than graphite. Evidence will also be presented on the graphitisation of polycrystalline diamond under extreme conditions. Further longer-term experiments are progressing since diamond offers enhanced performance [3] compared to other carbon materials for plasma facing wall applications. References[1] A.M. Stoneham, J.R. Mathews, I.J. Ford, Innovative materials for fusion power plant structures: separating functions, J. Phys. Condens. Matter, 16 (2004) S2597.[2] S. Porro, G. De Temmerman, S. Lisgo, P. John, I. Villalpando, J.W. Zimmer, B. Johnson and J.I.B.Wilson, Nanocrystalline diamond coating of fusion plasma facing components, Diamond and Related Mater., 18 (2009) 740. [3] D.M.Duffy, Fusion power: a challenge for materials science, submitted for publication.
10:00 AM - J5.2
First Stages of Diamond BEN Nucleation on Iridium: An in situ Study by Electron Spectroscopies.
Anthony Chavanne 1 2 , Jean Charles Arnault 1 , Julien Barjon 2 , Philippe Bergonzo 1 , Pierre Galtier 2
1 , CEA, Gif sur Yvette France, 2 GEMaC, CNRS UMR-8635, Meudon France
Show AbstractSynthesis of highly oriented diamond thin films on hetero-substrates and the control of their doping are required towards improved performances of large area diamond devices for electronic and detection applications. The bias enhanced nucleation (BEN) treatment coupled with the MPCVD technique is the most efficient for diamond heteroepitaxy. At the present stage, the best oriented diamond films have been deposited on iridium [1], [2].Compared to other hetero-substrates, iridium presents favourable physical properties for diamond epitaxy (reduced lattice misfit, cubic structure and high melting point). Moreover, in CVD deposition, the substrate interaction with reactive carbon species is a key parameter which governs the interface formation and greatly influences the nucleation mechanisms. The weak interaction of iridium with carbon (no carbide formation) leads to a unique nucleation scheme [3] [4]. The knowledge of the surface evolutions induced by plasma exposures is essential to control the diamond / iridium interface. In this study, the first stages of diamond nucleation have been analysed step by step using different in situ techniques in a MPCVD reactor connected to an UHV analysis chamber. More precisely, this study will follow chemical evolutions of the iridium (100) buffer layer on SrTiO3 (100) along the successive steps (stabilisation under H2/CH4 plasma, short bias enhanced nucleation and early stages of growth). This allows the fine investigation of the deposited carbon layers and especially at the first stages of diamond nucleation by X-ray Photoelectron Spectroscopy (XPS) and Auger Electron Spectroscopy (AES). As a complement, ex-situ SEM analysis will be presented.Keywords: heteroepitaxy, iridium, plasma surface interaction.[1] K. Ohtsuka et al. , Jpn. J. Appl., Phys. Vol.35 (1996).+[2] M. Schreck et al. , Appl. Phys., Lett. 74,5 (1998).[3] M. Schreck et al. , Dia. Rel. Mat., 12,3-7 (2003).[4] M. J. Verstraete et al, Appl. Phys., Lett. 86 (2005).
10:15 AM - J5.3
Characterization of Nano-crystalline Diamond Films Grown Under Continuous DC Bias During Plasma Enhanced Chemical Vapor Deposition.
Vincent Mortet 1 2 , L. Zhang 3 , M. Eckert 4 , A. Soltani 5 , J. D Haen 1 2 , O. Douheret 6 , E. Neyts 4 , D. Troadec 5 , P. Wagner 1 2 , A. Bogaerts 4 , S. Van Tendeloo 3 , K. Haenen 1 2
1 Institute for Materials Research , Hasselt University, Diepenbeek Belgium, 2 Division IMOMEC, IMEC vzw, Diepenbeek Belgium, 3 Electron Microscopy for Materials Science , University of Antwerp, Antwerp Belgium, 4 Research group PLASMANT, University of Antwerp, Antwerp Belgium, 5 Composants et Dispositifs microondes de puissance, Institut d'Electronique de Microélectonique et de Nanotechnologie, Villeneuve d'Ascq France, 6 Service de la Chimie des Materiaux Nouveaux, MateriaNova Research Center, Mons Belgium
Show AbstractNano-crystalline diamond (NCD) films have generated much interested due to their diamond-like properties and low surface roughness. Several techniques have been used to produce re-nucleation, such as hydrogen poor or with high methane concentration plasmas.In this work, we have studied the properties of diamond films grown on silicon substrates by plasma enhanced chemical vapor deposition using a continuous DC bias voltage during the complete duration of growth in a conventional methane and hydrogen gas mixture. Under specific bias deposition conditions, NCD films have been obtained.Subsequently, the layers were characterised by several morphological, structural and optical techniques. Besides a thorough investigation of the surface structure using SEM and AFM, special attention was paid to the bulk structure of the films. The application of FTIR, XRD, multi wavelength Raman spectroscopy (UV to NIR), TEM and EELS, yielded a detailed insight in important prop